180 SIDNEY F. HARMER. 
receives from the inspection of colonies of different ages, that 
polypides in old zocecia, which have no brown bodies, are dis- 
tinctly larger than those commonly met with in younger colo- 
nies in which brown bodies are present in the same zoccia. 
‘ The significance of the larger size of these older polypides is, 
as I take it, that they have gone on growing after the time 
when degeneration would have taken place in a younger colony. 
The difference in the size of the polypides, at different ages of 
the colony, becomes very apparent in comparing the size of 
the brown bodies formed from their degeneration. The 
diameter of the fertile brown body in young colonies is about 
‘05 mm.; that of a fertile brown body belonging to a later 
generation (fig. 36), and formed in colonies in which large 
polypides are present, may be as much as ‘09 or ‘10 mm. 
It is not always easy to decide, in a given case, whether the 
appearance of the alimentary canal implies the passage of a 
regular brown body into the canal or the partial degeneration 
of part of the epithelium. I have no doubt that the old brown 
bodies may be removed by passing into the alimentary canal of 
the newly formed polypide, as in Flustra and some other 
Polyzoa. Although one or even two brown bodies may occur 
in a single zoecium of Lichenopora verrucaria, I do not 
think I have ever found more than two; and in most cases 
where a polypide has recently degenerated, one does not find 
an older brown body as well, even though the age of the colony 
makes it certain that there has been an older brown body. In 
some of these cases it is probable that the old brown body 
fuses with the degenerating polypide; but in others it may be 
that the old brown body has passed into the alimentary canal 
before the degeneration of the polypide again takes place. 
Some of my sections indicate the occurrence of this process, 
and the brown body seems to become attached to the wall of 
the stomach, and finally to pass into it. Nuclear structures 
and other parts of the brown body may in these cases occur 
freely in the lumen of the alimentary canal. Even without 
actual evidence of this kind it would almost be necessary to 
assume that this takes place; for in no other way do I see any 
